Electronics guys, need advice

so im attempting to modify a CDI unit to work on my bike. the CDI unit however requires a steady DC current supply instead of the AC that my magneto is putting out. according to a little reasearch I did, I am gonna need a certain type of rectifier and capacitor to supply steady DC current to the cdi unit. The cdi unit was designed to run of a battery, however im trying to avoid using one at all. Is this even possible?